This sample chapter discusses what ASP.NET has to offer. Learn the system requirements for implementing an ASP.NET application, how to install the ASP.NET Framework on your system, what tools can be used to create ASP.NET applications, how to create an ASP.NET page, and how to view the output of your ASP.NET pages.

This chapter is excerpted from Sams Teach Yourself ASP.NET in 24 Hours.

From the author of

From the author of

ASP.NET is a new Internet programming technology from Microsoft that applies
a more streamlined, object-oriented approach to building dynamic Web
applications. With existing Active Server Pages technology, server-side code is
intermingled and interspersed with client-side HTML. This often results in
large, complex pages of code, where following the logic of the program can be
difficult at best, especially if you are new to programming.

In this hour, you will learn more about what ASP.NET has to offer. To be more
specific, you will learn

What ASP.NET is

What the system requirements are to implement an ASP.NET
application

How to install the ASP.NET Framework on your system

What tools can be used to create ASP.NET applications

How to create an ASP.NET page

How to view the output of your ASP.NET pages

What Is ASP.NET?

In the early days of Internet Web site design and development, technologies
were limiting. Static HTML pages served up the necessary information that a
person wished to convey to his audience. Because technologies were more limiting
back then, it was easier to get away with a site that was not as interactive as
it needed to be. Nowadays, however, it is important to learn how to build
dynamic, interactive Web sites, especially with the increasing use of multimedia
elements such as Flash and Shockwave and the development of e-commerce and
e-business sites that require database integration.

To meet this need, Microsoft created a Web-development platform called
Active Server Pages, or ASP. ASP was widely used and accepted
throughout the industry because most developers could utilize their existing
Visual Basic or VBScript skill sets when developing Web applications.

Despite this widespread acceptance, using Active Server Pages was limiting in
some respects. For example, validation of form data sometimes required extensive
coding on both the client browser and the server. Also, some aspects of Active
Server Pages were not scalable in an enterprise environment and didn't
function robustly in high-volume sites (although there were ways around these
problems). In addition, combining server-side code on the same page as HTML and
JavaScript often resulted in Web pages that were a convoluted mixture of
server-side logic code and fancy HTML code designed for the user interface,
which among other problems made code maintenance a real issue.

To overcome these problems and many others, Microsoft has introduced
ASP.NET—its next-generation Web development environment. If you have
experience in programming applications, you will find that the ASP.NET Framework
is very similar to building client/server applications. Even if you've
never written a line of code in your life, you will find that ASP.NET is a
relatively easy programming language to learn.

Is ASP.NET Browser Specific?

ASP.NET is a browser-independent programming model. ASP.NET will run on the
latest versions of Internet Explorer and Netscape Navigator, as well as on other
widely used browsers, such as Opera. Also, ASP.NET applications will gracefully
downgrade to older versions of Internet Explorer and Netscape Navigator. This
means that the vast majority of users on the Internet will be able to use your
Web applications without you needing to write browser-specific code. This
feature takes a great burden off the shoulders of current Web developers,
although it is still important to be aware that not all browsers accept Dynamic
HTML (DHTML) in the same way. For instance, Netscape Navigator versions 4.0
through 4.75 do not allow text properties, like color and font, on the page to
be changed unless the page is reloaded in the browser. Internet Explorer
versions 4.0 and higher, on the other hand, do allow text properties to be
changed on the page. These inconsistencies, and many others, still need to be
considered when writing client-side code.

What Programming Languages Can Be Used with ASP.NET?

The .NET Framework specifies that applications can be written in any
programming language that supports the Common Language Runtime (CLR). The Common
Language Runtime translates any CLR-compliant application to Microsoft
Intermediate Language (IL). This intermediate-level code is then compiled for
the platform where it will be executed. This simple process allows you to create
an application in one language that can be used on any operating system using
CLR. Furthermore, you can take an application that is written in one programming
language and use it in an application that is written in a completely different
programming language. No longer do you have to learn a completely different
programming language whenever a new technology is released.

For the latest version of the .NET Framework, Microsoft is releasing four
different languages that can be used to write CLR-specific code. These languages
are Visual Basic.NET (also known as VB.NET), C# (pronounced
C-sharp), C++.NET, and JScript.NET. Third-party languages are also being
developed such as Perl, Smalltalk, and Cobol, with more languages expected to
join the list as the technology becomes more prevalent. Here's a brief
description of each of these Microsoft languages:

Visual Basic.NET: VB.NET is a relatively easy programming language to
learn. It is considered a high-level programming language, which means that its
syntax is close to human languages and not similar to machine languages, such as
Assembly. Of the programming languages mentioned in this section, VB.NET is
probably one of the easiest languages to learn. For this reason, all the code
examples in this book will be written in VB.NET.

C#.NET: C# is a simple, modern, object-oriented, type-safe programming
language derived from C and C++. C# aims to combine the high productivity of
Visual Basic and the raw power of C++. This language is geared toward more
accomplished developers who are used to the somewhat-cryptic structure of C++.
Beginning developers are advised to start with Visual Basic and then move on to
C#.

Visual C++.NET: Visual C++.NET is the next iteration of Microsoft's
existing Visual C++ programming language, which is a powerful, object-oriented
programming language. Typically, this language is used to create very complex
and sophisticated applications.

JScript.NET: JScript is a powerful scripting language targeted
specifically at the Internet. It is also the first scripting language to fully
conform to ECMAScript—the Web's only standard scripting language. This
language is similar in syntax to C# and C++, although it is a little easier to
implement.

What Is Needed to Run ASP.NET?

In order to run ASP.NET pages, you will need to configure a computer with the
.NET Framework installed. As of this writing, the .NET Framework is supported on
Windows NT 4.0, Windows 2000, and Windows XP. However, Windows NT 4.0 with
Service Pack (SP) 6a or Windows 2000 with SP 2 is strongly recommended. You will
also need to install Internet Explorer 5.5 and Microsoft Data Access Components
(MDAC) 2.6 as prerequisites to the .NET Framework. In addition, if you are not
running Windows 2000, you must install Internet Information Server (IIS), known
as Personal Web Server (PWS) in Win9X and Me. IIS 5.0 could be easily
added to Windows 2000 Professional via Add/Remove Windows Components in the
Control Panel. Make sure the IIS service has been started.